What developer volume should I use?

10 vol (3%) for deposit-only colour and darker shades. 20 vol (6%) for standard permanent colour with 1-2 levels of lift. 30 vol (9%) for 2-3 levels of lift. 40 vol (12%) for high lift tints with 3-4 levels of lift. Never use 40 vol on the scalp for sensitive clients.

Does the ratio change with different developer volumes?

The mixing ratio (e.g. 1:1 or 1:2) stays the same regardless of developer volume. You change the volume to control lift, not the ratio. The ratio is set by the manufacturer for the specific product type. However, some toners and glosses use a different ratio (often 1:2) than permanent colours (typically 1:1).

What is the difference between volume and percentage?

10 vol = 3%, 20 vol = 6%, 30 vol = 9%, 40 vol = 12%. Volume refers to the amount of oxygen released (10 vol releases 10 times its volume in oxygen). Percentage refers to the hydrogen peroxide concentration. Both scales measure the same thing — the strength of the developer.

Can I mix two developer volumes together?

Yes, you can mix equal parts of two volumes to get an intermediate strength. For example, equal parts 20 vol and 30 vol gives approximately 25 vol. This is useful when you need a strength between standard volumes. Always mix thoroughly before adding colour.

CutCalcs

Developer Ratio Calculator — Colour to Developer Proportions

Work out the correct amount of developer for any colour quantity and mixing ratio.

Colour Weight

Weight of colour cream or tube

Mixing Ratio

Developer Volume

How We Calculate This

The calculator multiplies your colour weight by the developer ratio to determine how much developer you need. It also shows the percentage strength equivalent and expected lift capability.

The formula

Developer weight = Colour weight x (Developer part / Colour part)

For a 1:1 ratio: Developer = Colour weight x 1

For a 1:1.5 ratio: Developer = Colour weight x 1.5

For a 1:2 ratio: Developer = Colour weight x 2

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always perform a strand test before chemical services.